Leptobrachium boringii

Leptobrachium boringii exhibits sexual selection in a striking way. Male Leptobrachium boringii exhibit conspicuous keratinized nuptial spines that grow on their upper lip during the breeding season—these are the "moustache" and "spines" referred to in its common names. Moreover, male Leptobrachium boringii are larger, on average 75 mm (3.0 in) in snout-vent length, than females, which are on average 67 mm (2.6 in) in SVL (female-biased sexual size dimorphism is more common in frogs[4]). These unusual features seem to relate to male–male combat for best breeding territories and/or female preference for larger males. However, also multiple paternity could be observed, suggesting that some males use the sneaker strategy to fertilize eggs, instead of defending territories.[3]